Help a fellow dad - abortion and the rights of a father?

We've had a pretty tricky enquiry from a dad in the US about a father's rights when it comes to abortion. If you know anything about this, would be great if you could comment on this post. Here's the background:

I have been supportive of the decision of my girlfriend having an abortion. Yes she made the decision and all I could do was try to do my best to be there for her, trying to be the strong one. I was devastated about it because I didn't want it to happen. She and I did talk about it. But rather than lose both of them, I chose to lose my child and have the mother still in my life. There are a lot of emotions dealing with the loss of a child for both the mother and the father.

Before I was in a relationship, I was in a situation where I wanted the woman to have an abortion. She did not.